System for transport by passive vehicles

ABSTRACT

A transport system for passive vehicles which move by way of wheels on treadways of a track includes guide surfaces for guiding the vehicles along the track. Each vehicle includes at least one drive roller propelling the vehicle through contact with rotary tubes. An axis of the drive roller is steerable with respect to the axis of the tubes. The vehicle also includes guide rollers adapted to cooperate with guide surfaces of the track. The track includes a trench containing the rotary tubes and a cover disposed atop the trench and having a lengthwise slit.

BACKGROUND OF THE INVENTION

The invention relates to a system for the transport by passive vehiclesof the type in which the vehicles are moving with the assistance ofwheels onto treadways of a track. As a way of ensuring the displacementof the vehicles, a series of rotary tubes are arranged without anydiscontinuity in the longitudinal direction of the track, and means forguiding the vehicles along the latter we provided, Each vehiclecomprises at least two bogies carrying displacement wheels, at least onedrive roller for propelling the vehicle through frictional contact withthe outer peripheral surface of the rotary tubes and the axis ofrotation of which is steerable with respect to the axis of the tubesthrough pivoting about a substantially vertical axis between a positionparallel to the tubes in which the rollers do not propel the vehicle anda position of maximum propulsion, and a device for guiding the vehicleadapted to co-operate with the guide means of the track.

The transport systems of this kind, which are known, exhibit the majorinconvenience of requiring a relatively complex and expensiveinfrastructure and equipment on the vehicles intended to co-operate withthis infrastructure with a corresponding complexity.

These systems in view of their excessive costs of installation andoperation are not competitive with respect to other known transportsystems, such as tramways. Thus the advantage of much bettercompatibility with the environment than the known systems are broughtinto disrepute by the above-mentioned economical inconveniences.

SUMMARY OF THE INVENTION

The present invention has as its object to propose a transport system ofthe type stated hereinabove which exhibits an even lower cost ofinstallation and operation than the other competing transport systemswhile further increasing its environmental or ecological advantage.

To reach that goal, the transport system according to the invention ischaracterized in that the guide means of the track are formed of twoparallel surfaces advantageously extending symmetrically with respect tothe vertical middle plane of the track along the latter and in that thedevice for guiding each vehicle comprises wheels mounted onto a supportmade fast to the bogies so as to bear upon the guide surfaces.

According to one characteristic of the invention, the device forsteering the propelling drive rollers is formed of an electric stepmotor.

According to another characteristic of the invention the transportsystem comprises a central control station adapted to dialogue with anemitter/receiver device on board each vehicle and the track is dividedinto sectors to each one of which is assigned a set speed in accordancewith the topography of the track sector and if need be with the locationwith respect to the foregoing vehicles.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention would be better understood and further objects,characteristics, details and advantages thereof will appear more clearlyin the explanatory description which will follow, made with reference tothe attached diagrammatic drawings given by way of example onlyillustrating an embodiment of the invention and in which:

FIG. 1 is a perspective view of the system for the transport by passivevehicles according to the present invention;

FIG. 2 is a simplified front view of the lower part of a vehicleaccording to the present invention;

FIG. 3 is a sectional view on a larger scale with parts broken away ofthe detail shown at III in FIG. 1; and

FIG. 4 is a block diagram of an automatic control system for a vehicleaccording to the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows one portion of a track 1 on which is travelling a vehicle 2in particular for the transport of passengers, of which only both bogies3 carrying two wheels 4 and the lower portion comprising two propellingdrive devices 5 and two guide devices 6 each one associated with a bogieare shown.

The track 1 comprises a trench 8 which includes two parallel sidesurfaces 9 located in front of each other and extending in substantiallyparallel relation to the axis of the track symmetrically with respect tothe vertical longitudinal middle plane of the latter. Each one of thetwo faces is adapted to constitute a face for the guiding of thevehicles circulating on the track. The lower portion of the trenchcomprises two inclined faces 10 shaped as the legs of a V which join oneof the vertical side faces 9 upwards and the horizontal bottom 11 of thetrench downwards. The trench is covered at the level of the ground withtwo plates 15 leaving a slot therebetween extending along the axis ofthe trench. The wheels 4 are moving upon treadways 7 provided on theground on either side of the trench.

Along the axis of the latter at some distance of the bottom 11 and ofthe inclined walls 10 is arranged a series of rotary tubes 13 which areaxially aligned. The tubes are mounted onto conical bearings endwise soas to ensure their being held along any axes. Over the whole track theyare positioned upon bearings arranged at regular intervals of 4 metersfor example. By way of example the tubes are of steel with a diameter of244 mm for a thickness of 6.3 mm. The tubes are driven in one singledirection of rotation at a constant speed on the order of 800revolutions per minute, for example. The series of tubes is divided intosections and the motors for the rotary drive of the sections havediffering powers according to the nature and the length of the sections.One may, for example, provide motors for acceleration and slopes capableof rotating 80 meters of tube and motors for keeping the speed constant,capable of rotating 120 meters of tube.

The transmission of the torque may be carried out in any suitable knownmanner such as with the assistance of a toothed belt engaged with amotor-reducer set in relation to the characteristics of the motor. InFIG. 1, the drive motors for rotating the tube sections are not shown. Astand-by motor 12 is shown arranged between two tube sections so that itmay ensure the rotation of one or the other section. Reference numeral14 indicates a torque transmission device which is of the toothed belttype.

Each guide device 6 includes a platform 16 fixedly mounted underneath abogie 3 through a brace 17 shaped as a plate extending verticallythrough the slit defined between both plates 15 covering the trench 8.Being thus located inside of the trench, the platform comprises twopairs of guide rollers 19 with vertical axes of rotation, each pairbeing arranged so as to bear upon one of the vertical guide surfaces 9of the track. Between both rollers 19 of each pair is arranged anemergency brake designated at 20. Both bogies of the vehicle areconnected by a longitudinal beam 22 which is pivotally connected at eachone of its ends at 23 to a platform 16. The beam thus extends axiallywithin the trench 8 as shown in FIG. 2. This same figure further showsthat the chassis of the vehicle identified by 25 is mounted for rotationabout a vertical axis on each bogie 3 with the assistance of two rings26, 27 made fast to the chassis and to the bogie, respectively.

As clearly shown in FIGS. 1 and 3, the connecting beam 22 carries bothpropulsion devices 5, each one being arranged near one bogie in theaxial space therebetween.

Each propulsion device 5 comprises a drive roller propelling throughfrictional contact 30 and having an axle 31 accommodated in a U-shapedsupport forming a yoke 32 directed vertically. The base of the yoke 32is fastened to a rod 33 which is made fast at its free and to and forunitary rotation with a gear 34 meshing with a countergear 35 having ahorizontal shaft made fast through a declutching device 36 to and forunitary rotation with the output shaft of an electric motor 37 in theform of a stepper motor. The rod 33 is rotatably mounted and axiallyretained with the assistance of a collar 38 in a support 40 mounted forbeing vertically displaceable on the beam 22.

The support 40 comprises a horizontal top platform 41 the central areaof which is shaped as a housing portion 42 for the collar 38 of the rod33. The platform of rectangular shape 41 carries at the level of eachone of its corners a vertical brace 43. Owing to its braces, the support40 is mounted straddlewise onto the beam 22 so as to prevent the supportfrom any motion other than the vertical one. The mounting of the supportonto the beam ensures a side guiding effect to the support. Those endsof both braces located at each longitudinal end of the support 40 carrya horizontal platform 44 which extends outwards of the support 40 alongthe axis of the vehicle. Between each platform 44 and the connectingbeam 22 is positioned a helical spring 46 the axis of which extendsvertically. This spring has the purpose of pushing the propelling roller30 against the outer peripheral surface of the rotary drive tube 13 asshown clearly in FIG. 3.

Since the step motor is mounted onto the top platform 41 of the support40 and the rod 33 supporting the roller 30 extends through the beam 22so as to be freely rotatable, any rotation of the output shaft of thestepper motor 37 causes a pivoting of the roller in the direction of thearrow F and thereby a variation of the direction of the axis of rotation31 of the roller with respect to the axis of the tube. Since the rolleris pushed by the springs 46 against the tube 13, the rotation of thelatter is transmitted through friction to the roller which then causesthe displacement of the vehicle with a speed which depends upon theorientation of the roller with respect to the tube.

When the axis of the tube 13 and the axis 31 of the roller are parallel,the tube and the roller are rotating but generate no motion-generatingreaction. As soon as another orientation is given, the resistanceinduced by friction causes a force which propels the vehicle. Theoptimum of the conversion is reached when the angle involved is from 45°to 60°. Thus the speed variations necessary for the acceleration, forthe slowing down and for the braking of the vehicle are obtained by asuitable change of the angle formed between the axes of the rollers andthe tube, caused by the actuation of the step motor 37.

As shown in FIG. 1, one single step motor 37 is sufficient to ensure thesynchronous steering of both drive rollers 30. This effect is obtainedowing to a connection between the rods 33 provided in the example shownas a parallelogram 48 comprising two links 49 which are parallel to theaxis of the vehicle and connected by two connecting links 50 each one ofwhich is secured to be made fast at its central portion to and forunitary rotation with the rod 33 steering a roller 30 in the mannerillustrated in FIG. 3. Thus the rotary motion imparted to the rod 31 ofone of the rollers is transmitted to the rod of the other one.

As to the structure of the vehicle, it should further be noted thatdynamos 52 are mounted on the axles 31 of the rollers 30, which formpart of an autonomous device for the electric power supply of thevehicle.

At each end of the vehicle is provided a device 53 for coupling thevehicle to another vehicle, which is pivotally connected to one end of arod 55 the other end of which is pivotally connected to one vertex ofthe parallelogram 48.

The control of the vehicles according to the invention is done entirelyautomatically. For that purpose, the system according to the inventioncomprises a central control station shown in FIG. 4 which manages allthe vehicles. In order that this station may accomplish this task, thetrack is divided into sectors each one of which is fitted with a controland regulation emitting-receiving circuit loop. Each vehicle is fittedwith an emitter-receiver device enabling it to dialogue with the centralstation through the medium of a control and regulation circuit loop.When moving past such a sector circuit loop, the vehicle transmits tothe central station an identification message and the state parametersof the different components of the equipment of the vehicle. In return,the vehicle receives the speed setting for the following sector. The setvalue is accompanied by a variable stating the type of accelerationvariation curves to be complied with as defined by the program ofmanagement of the travel. Two variation curves are stored for eachsector, namely the standard acceleration and deceleration curve inparticular in accordance with the topography or the geometry of thetrack in this sector and an emergency deceleration curve. These curvesare stored in one part of the emitter-receiver device of the vehiclewhich constitutes the interface with the step motor. This part isdesigned to monitor the proper operation of the vehicle and to detectany bad transmission of data.

The circuit loops, preceding the one which has given the speed settingand is identifiable by the central station owing to the identificationmessage from the vehicle, emit upon an order from the central station,information about a variation for example of 5 to 0 km/hour for thefirst circuit loop (located for example at 40 m), of 30 to 5 km/hour forthe second circuit loop (located at 80 m), of 43 to 30 km/hour for thethird circuit loop (located for example at 120 m), and of keeping thespeed of 43 km/hour for the fourth circuit loop (located at 160 m). Tofurther improve the safety, a safety circuit loop is provided upstreamof the circuit loop moved past by the vehicle. The circuit loops whichhave just been stated will be counted from this safety circuit loop.Since the normal spacing between two vehicles is 200 meters in thisexample corresponding to 5 sectors, the slowing down settings producetheir effect in case of a malfunction only. Thus the emitted informationevolve in this fashion in accordance with the sensed presence of thevehicles by the management of the four circuit loops located upstream.

The collection and transmission of the information requires dataconcentrators distributed along the track. The track-vehiclecommunications are made secure by protocols for the checking oftransmission of the data. The data processing system of the centralstation centralizes those kinematic data which are characterizing eachvehicle. When moving past a circuit loop at a time t, knowing the speedand the distance to the next circuit loop, the central stationcalculates the travel time tp and thus establishes the anticipation ofthe presence of the vehicle at the time t+tp in the area of the circuitloop of the following sector.

When the vehicle passes over the next circuit loop at the anticipatedtime detectable by the emission of its identification message, thecentral station verifies the nominality of the travel of this vehicle.If on the contrary the identification message does not reach the centralstation at the expected times the latter concludes that there is amalfunction and starts the impaired mode of operation which will bedescribed subsequently.

In this case, the following vehicle is put in a slow speed andmechanically couples itself to the broken-down vehicle.

The assembly of both vehicles moves at a reduced speed to the nextstation where all the passengers alight. Both empty vehicles are thencarried at normal speed to the garage-workshop. The parallelogramensures the positioning of the rollers of the broken down vehicle to bethe same as the position of the rollers of the pushing vehicle.

In the case of a bad transmission or of an erroneous transmission of theinformation from the circuit loops or of the detection of an anomaly onboard the vehicle, the vehicle puts itself into the safety conditionproviding for an emergency stop of the vehicle, an unclutching of thestep motor and thereby putting the operation into the impaired mode.

It should further be noted that for safety reasons, the propellingrollers automatically return to the position perpendicular to the tubesas soon as there is no longer any action of the motor 37 provided toimpart the orientation of the roller in accordance with the set datagiven by the system.

In the foregoing description, the control has been described for onesingle vehicle. Several vehicles, however, may be gathered to form agroup then considered as one single vehicle by the system.

The system according to the invention of course permits the formation ofgrid networks.

I claim:
 1. A transport system for passive vehicles comprising:a trackcomprising first and second treadways, a trench disposed between thetreadways and having first and second lateral guide surfaces, and astationary cover which covers the trench and has a slit extending in alengthwise direction of the track; a plurality of rotary tubes disposedin the trench and arranged in series in the longitudinal direction ofthe track; and a vehicle comprising first and second bogies each havingtwo main wheels, each main wheel being disposed on one of the treadwaysfor supporting the vehicle, a drive roller contacting one of the rotarytubes and being steerable about a steering axis between a position inwhich an axis of rolling of the drive roller is parallel to an axis ofthe rotary tube which it contacts and a maximum propelling position, apair of braces each having a first end connected to one of bogies and asecond end extending through the slit of the cover into the trench, asupport connected to the second end of each brace within the trench, anda pair of guide wheels rotatably mounted on each support, each guidewheel being in rolling contact with one of the guide surfaces of thetrack.
 2. The system according to claim 1 including a step motorassociated with the drive roller for steering the drive roller about itssteering axis.
 3. The system according to claim 1 wherein the vehicleincludes a beam disposed in the trench and extending in a lengthwisedirection of the vehicle and pivotably connected to the supports.
 4. Thesystem according to claim 1 wherein the drive roller is mounted forrotation in a support carrying a rod which extends perpendicular to anaxis of rolling of the drive roller and is rotatably mounted in asupport mounted on a beam so that the drive roller may carry outvertical motion against a biasing member adapted to push the driveroller into contact with the surface of one of the rotary tubes, the rodbeing adapted to be rotated by a step motor to steer the drive rollerabout its steering axis.
 5. The system according to claim 4 wherein thevehicle includes an autonomous electric power supply comprising a dynamoconnected to an axle of the drive roller.
 6. The system according toclaim 2 wherein the vehicle includes two steerable drive rollers, eachconnected to one of the bogies, and a parallelogram-shaped linkageconnecting both drive rollers to the step motor.
 7. The system accordingto claim 1 wherein the cover is flush with the treadways.
 8. The systemaccording to claim 1 wherein the trench is recessed with respect to aground surface.
 9. A transport system for passive vehicles comprising:atrack comprising first and second treadways and first and second lateralguide surfaces extending in a lengthwise direction of the track betweenthe treadways; a plurality of rotary tubes arranged in series in thelongitudinal direction of the track; a plurality of vehicles each havingmain wheels disposed on the treadways for supporting the vehicle, adrive roller contacting one of the rotary tubes and steerable about asteering axis between a position in which an axis of rolling of thedrive roller is parallel to an axis of the rotary tube which it contactsand a maximum propelling position, and a plurality of guide wheels, eachguide wheel being in rolling contact with one of the guide surfaces ofthe track; and a central control station adapted to dialogue with anemitter-receiver device on board each vehicle, wherein the track isdivided into track sectors to each of which is assigned a set speed inaccordance with a topography of the track sector, and each track sectorcomprises an emitting-receiving control and regulation circuit loopconnected to the central control station to ensure dialogue with theemitter-receiver devices of the vehicles.
 10. The system according toclaim 9 wherein the central control station is adapted to calculate thetime at which each vehicle should pass over each track sector and tocompare the calculated time of passage to an actual time of passageindicated by the emitter-receiver device of the vehicle.
 11. A transportsystem for passive vehicles comprising:a track divided into a pluralityof track sectors and comprising first and second treadways and first andsecond lateral guide surfaces extending in a lengthwise direction of thetrack; a plurality of rotary tubes arranged in series in thelongitudinal direction of the track; and a plurality of vehicles eachhaving main wheels disposed on the treadways, a drive roller contactingone of the rotary tubes and steerable about a steering axis between aposition in which an axis of rolling of the drive roller is parallel toan axis of the rotary tube which it contacts and a maximum propellingposition, and a plurality of guide wheels, each guide wheel being inrolling contact with one of the guide surfaces of the track, whereineach vehicle is adapted to receive a speed setting for a successivetrack sector and a variable indicating a type of acceleration variationcurve to be complied with, and wherein for each track sector, a standardacceleration and deceleration curve corresponding to one of a topographyand geometry of the track sector in which the vehicle is located and anemergency deceleration curve are stored in an emitter-receiver device ofthe vehicle.
 12. The system according to claim 11 wherein in case of anabnormality in a first one of the vehicles, the first vehicle putsitself into a safety condition ensuring an emergency stop of the firstvehicle and operation in an impaired mode is provided for a secondsucceeding vehicle on the track, providing coupling of the secondvehicle to the first vehicle which underwent the abnormality and commondisplacement of both vehicles at a reduced speed to a next normal stopstation.
 13. A transport system for passive vehicles comprising:a trackcomprising first and second treadways and first and second lateral guidesurfaces extending in a lengthwise direction of the track; a pluralityof rotary tubes arranged in series in the longitudinal direction of thetrack; and a plurality of vehicles each having main wheels disposed onthe treadways, a drive roller contacting one of the rotary tubes andsteerable about a steering axis between a position in which an axis ofrolling of the drive roller is parallel to an axis of the rotary tubewhich it contacts and a maximum propelling position, a motor associatedwith the drive roller for steering the drive roller about its steeringaxis, and a plurality of guide wheels, each guide wheel being in rollingcontact with one of the guide surfaces of the track, the drive rollerbeing adapted to return automatically to the position in which its axisof rolling is parallel to the axis of the rotary tube which it contactsupon a stop of operation of the motor.